/Engine/Source/Runtime/ApplicationCore/Public/GenericPlatform/Accessibility/GenericAccessibleInterfaces.h
Retrieves the widget before this one in the parent's list of children. This should return nullptr for the first widget.
The previous widget on the same level of the UI hierarchy.
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [IAccessibleWidget](API\Runtime\ApplicationCore\GenericPlatform\Accessibility\IAccessibleWidget) > GetPreviousSibling()